Soft-deprecating re.match()

Simon Willison's Blog News
python regex deprecation standard-library update

Summary

Python 3.15 soft deprecates the re.match() function, introducing re.prefixmatch() as a clearer alternative for pattern matching at the start of strings.

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Cached at: 09/11/26, 06:19 PM

# Soft-deprecating re.match() Source: [https://simonwillison.net/2026/Sep/11/soft-deprecating-re-match/](https://simonwillison.net/2026/Sep/11/soft-deprecating-re-match/) 11th September 2026 \- Link Blog **[Soft\-deprecating re\.match\(\)](https://hugovk.dev/blog/2026/soft-deprecating-re.match/)**\([via](https://lobste.rs/s/u7dr96/soft_deprecating_re_match)\) Python has a concept of[soft deprecation](https://peps.python.org/pep-0387/#soft-deprecation), where APIs are marked as "should no longer be used to write new code" without any promise/threat to remove them in the future\. Python 3\.15 release manager Hugo van Kemenade describes how in the upcoming 3\.15 release soft deprecation has come for the venerable but deeply confusing`re\.match\(\)`function\. It's now available with the much clearer alternative`re\.prefixmatch\(\)`name \- reflecting how it anchors at the beginning of the string but not the end\. Most of the time you probably want`re\.search\(\)`\(match this pattern anywhere in the string\) or`re\.fullmatch\(\)`\(match the entire string\) instead\.

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